<scp> ΔO <sub>2</sub> </scp> / <scp> N <sub>2</sub> </scp> ′ as a tracer of mixed layer net community production: Theoretical considerations and proof‐of‐concept
Bibliographic record
Abstract
Abstract We present a method to estimate net community production (NCP) from underway ΔO 2 /N 2 observations. This approach, based on high‐resolution measurements using relatively low‐cost O 2 ‐optode and gas tension device instrumentation, provides an alternative to NCP derivation from mass spectrometric analysis of ΔO 2 /Ar. To fully exploit ΔΟ 2 /Ν 2 as an NCP tracer, it is necessary to account for differences in surface water argon (Ar) and nitrogen (Ν 2 ) saturation states. Using a one‐dimensional mixed layer model, evaluated against field observations, we examined the divergence between ΔO 2 /Ar and ΔΟ 2 /Ν 2 resulting from various physical processes. Results show that changes in sea surface temperature, bubble injection and vertical mixing can decouple mixed layer ΔO 2 /Ar and ΔΟ 2 /Ν 2 , while biological N 2 ‐fixation has a negligible effect. Based on readily available environmental data, we developed a framework to correct for Ar and N 2 solubility differences, yielding a new tracer, ΔΟ 2 /Ν 2 ′, that is a near‐analog of ΔO 2 /Ar. Through model simulations and field measurements, we show that ΔΟ 2 /Ν 2 ′ provides an excellent approximation to ΔO 2 /Ar, and that uncertainty and biases in ΔO 2 / N 2 ′ are small relative to other errors in NCP calculations. This work demonstrates the potential for ΔO 2 / N 2 ′ measurements to significantly expand NCP estimates from a variety of sampling platforms.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".